A person of interest in Arizona

Authorities release photograph of a "person of interest" in a mass shooting that wounded an Arizona Congresswoman. Deborah Lutterbeck reports

USA-SHOOTING - Authorities in Arizona release a photograph of a "person of interest" following a shooting spree in Tucson that severely wounded a congresswoman, killed six people and left another twelve wounded at a shopping center.

Authorities arrested a suspected gunman identified as 22 year-old Jared Lee Loughner, shortly after the shooting. The suspicion was that he had not acted alone.

Pima County Arizona Sheriff Clarence Dupnik

Pima County Sheriff Clarence Dupnik, saying):

"There's some reason to believe that he came to this location with another individual."

That "person of interest" is seen in a surveillance photo inside a store at the shopping center released by authorities.

Police seeking a motive for the shooting spree are looking at a trail of anti-government messages on the Internet left either by Loughner or someone writing under that name. There is no coherent theme to the messages.

Doctors are optimistic that Congresswoman Gabrielle Giffords, shot in the head, will survive.

A Federal Judge and a nine year old girl are among the dead.

Late Saturday evening, well-wishers gathered outside the Tucson University Medical Center for a candlelight vigil where Giffords is still fighting for her life.